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Generator question

Post in 'The Pellet Mill - Pellet and Multifuel Stoves' started by moralleper, Nov 13, 2008.

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  1. tinkabranc

    tinkabranc Minister of Fire

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    Thats ok, no need for explanation...I get even more confused every time I see threads on UPS.
    All I know is my IT friends recommended this one after I told them what I wanted one for
    and gave them the specs on the stove. So far, no issues.

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  2. Jester

    Jester New Member

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    Im running a 10K generac. I really ought to flip it on and see if it will power the stove well. I couldnt get any answers out of generac on it being pure sine or modified
  3. Richardin52

    Richardin52 Member

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    I have a Honda 600 watt generator that I have run a wood boiler on for 7 days once about ten years ago. Same circulator on the boiler now. I also ran a couple direct vent gas heaters that had blower with it. No problems.

    When I was running the boiler for 7 days that time I also ran the frig, TV, computer, lights, etc. on it, no problem. We just figured the watts we were running and stayed within the range of the generator. The circulator used 1/8 amp (15 watts) so we could run the boiler all the time and then ran one other thing also at the same time like the frig. or the computer. Worked great and it used 1 qt. of gas every 1 1/2 hrs.

    Does anybody know what Honda generators put out, clean, pure etc. sine wave?
    I was planning on using the same generator for the pellet stove if I needed to but now I'm a little spooked about doing that.
  4. pete324rocket

    pete324rocket Feeling the Heat

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    Here is a quote from a website about sine waves and inverters that seems straightforward so I'm gonna paste it...probably couldn't do a better job myself...plus less wear on the typing fingers! I realize that it doesn't cover generators specifically...BUT...the sine waves coming from the utility are from a rotating generator at a precise speed-60 hz or 60 cycles per second.Can your generator duplicate that? If not,then it must be conditioned with an invertor of sorts...as described in the following passage.

    POWER QUALITY -- SINE WAVE vs. "MODIFIED SINE WAVE"

    Some inverters produce "cleaner" power than others. Simply stated, "sine wave" is clean; anything else is dirty. A sine wave has a naturally smooth geometry, like the track of a swinging pendulum. It is the ideal form of AC power. The utility grid produces sine wave power in its generators and (normally) delivers it to the customer relatively free of distortion. A sine wave inverter can deliver cleaner, more stable power than most grid connections.

    How clean is a "sine wave"? The manufacturer may use the terms "pure" or "true" to imply a low degree of distortion. The facts are included in the inverter's specifications. Total harmonic distortion (THD) lower than 6 percent should satisfy normal home requirements. Look for less than 3 percent if you have unusually critical electronics, as in a recording studio for example.

    Other specs are important too. RMS voltage regulation keeps your lights steady. It should be plus or minus 5 percent or less. Peak voltage (Vp) regulation needs to be plus or minus 10 percent or less.

    A "modified sine wave" inverter is less expensive, but it produces a distorted square waveform that resembles the track of a pendulum being slammed back and forth by hammers. In truth, it isn't a sine wave at all. The misleading term "modified sine wave" was invented by advertising people. Engineers prefer to call it "modified square wave."

    The "modified sine wave" has detrimental effects on many electrical loads. It reduces the energy efficiency of motors and transformers by 10 to 20 percent. The wasted energy causes abnormal heat which reduces the reliability and longevity of motors and transformers and other devices, including some appliances and computers. The choppy waveform confuses some digital timing devices.

    About 5 percent of household appliances simply won't work on modified sine wave power at all. A buzz will be heard from the speakers of nearly every audio device. An annoying buzz will also be emitted by some fluorescent lights, ceiling fans, and transformers. Some microwave ovens buzz or produce less heat. TVs and computers often show rolling lines on the screen. Surge protectors may overheat and should not be used.

    Modified sine wave inverters were tolerated in the 1980s, but since then, true sine wave inverters have become more efficient and more affordable. Some people compromise by using a modified wave inverter to run their larger power tools or other occasional heavy loads, and a small sine wave inverter to run their smaller, more frequent, and more sensitive loads. Modified wave inverters in renewable energy systems have started fading into history.

    Just an addition to this. The inverter I use is a 1200 watt type that cost about 100 bucks and is a modified-sine wave but yet it operates my pellet stove when the cheapy generator will not. Specs are 115 volts RMS + or - 5% ,60 hertz + or - 1 hertz
  5. Richardin52

    Richardin52 Member

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    The way I understand it an inverter converts DC power to AC power and a modified sine wave has a square wave.

    That said most generators produce AC power so they are not inverting DC power at all, they are making true AC power. Because of that any generator that generates AC power would never produce a modified sine wave. A generator that produces DC power and then inverts it may however.

    Am I right or did I miss something
    .
  6. imacman

    imacman Guest

    No, you have it right. Inverters are only used to make AC from DC battery power, and they produce a square wave. An AC generator that works by rotating a rotor in a field of wires (stator) can initially only make "pure" waves.

    Given that, most of the generators we buy produce a somewhat "noisy" pure wave. But they should be fine for use with our stoves.
  7. crausch

    crausch New Member

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    Thanks for that last post Pete!

    I was unaware of the THD rating. I was looking between two generator models to purchase. The more expensive model (the one I really want) says it has a THD rating of less than 5. Given the quote above the generator should be fine for my stove. I guess the keyword is "should" be. The lower end model but still a nice generator, did not even list a THD rating. I think I'll go with the one confident enough to list it in their specs.
  8. pete324rocket

    pete324rocket Feeling the Heat

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    Yes,I checked the owners manual of my cheep generator and no mention of distortion. Also says 60 hertz but no mention of any variance there either.
  9. itworks

    itworks New Member

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    I just finished the test. I plugged my Harman P68 into my cheappie (ET&E;TG1200) using a 6 outlet surge protector and ran the stove for about 1/2 an hour. Everything seemed to work normally. I didn't use the auto ignite ,figuring that function may use too much juice.

    I guess we're ready for winter.
  10. ashes

    ashes Member

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    HI GUYS, PICKED UP ON YOUR THREAD CONCERNING INVERTERS (IN PART) AND NOTICED A LACK OF INFO FOR OTHERS WHOM MAY BE INTERESTED. FOR THOSE WHOM ARE INTERESTED IN INVERTERS, THEY SHOULD STAY WITH A QUALITY BRAND, SUCH AS, BUT NOT LIMITED TO "TRIPP LITE". THEY MANUFACTURE INVERTERS FOR ABOUT EVERY USE/SPEC, WHICH WILL ALSO RECHARGE YOUR BATTERY'S WHEN THE POWER RETURNS. BASICALLY YOUR LOOKING FOR A INVERTER SIZE THAT WILL SUPPLY THE "START UP"AMPS AND WATTS OF YOUR MOTOR. IF YOU TELL THEM THIS INFO FROM YOUR STOVE SPEC SHEET, THEY WILL ADVISE YOU WHAT SIZE YOU WILL NEED. (A ELECTRICIAN CAN ALSO DO THIS)

    ONCE YOU KNOW WHAT SIZE/MODEL YOU WANT SEARCH THE INTERNET, YOU CAN SAVE HUNDREDS BETWEEN VENDER'S.

    AS FAR AS BATTERIES ARE CONCERNED -- DO NOT USE A STANDARD UNSEALED AUTOMOTIVE/DEEP CYCLE BATTERY INDOORS ! (THE TYPE YOU CAN FILL WITH WATER) THEY GIVE OFF HAZARDOUS FUMES AND SHOULD NOT BE USED INDOORS.
    A QUALITY SEALED BATTERY WILL HAVE A "AH" RATING STAMPED ON IT. THE "AH" STANDS FOR AMP HOUR. THERE WILL BE A CHART SHOWING HOW MANY HOURS THE BATTERY CAN SUSTAIN THAT AMPERAGE. LOOK UP THE AMPERAGE OF YOUR STOVE AND FIND HOW MANY HOURS THE BATTERY SHOULD LAST. YOU WILL GET THE BEST RESULT WITH A GEL OR DEEP-CYCLE SEALED BATTERY.
    YOU CAN HOOK BATTERIES IN PARALLEL FOR A LONGER LIFE SPAN.
    THE USE OF THE STOVES GLOW PLUG FOR STARTING WILL GREATLY REDUCE THE BATTERY AMP-HOURS.

    THE ABOVE IS SOME BASIC INFORMATION YOU SHOULD CONSIDER. CONSULT A PROFESSIONAL
  11. hossthehermit

    hossthehermit Minister of Fire

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    ssssshhhhhhh.......
  12. Jester

    Jester New Member

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    Ive discovered that the generac produces a sine wave with less than 5% deviation, so its considered to be "clean"
  13. escobarmj

    escobarmj Member

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    Do you know approximately how long your stove will run on that backup? I have the same stove and am considering buying that APC unit. It looks like the price is about $150.
  14. tinkabranc

    tinkabranc Minister of Fire

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    My stove stays plugged into the UPS during the winter for short term blips and blinks in the power that we
    get during some storms. Most I have gotten out of it was 45 mins with the stove running on low.
    That gives me plenty of time to get the generator running if necessary.

    An inverter with batteries will last much longer, but I prefer not to go that route.
  15. Wet1

    Wet1 Minister of Fire

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    I looked into a small 2 stroke to run my pellet stove, but decided it wasn't the best choice for me. After loosing power last year when temps were in the single digits, my fear was that I still had to worry about my pipes freezing in the walls during the coldest periods w/o electricity. I ended up picking up a like new 7000w generator on CL ($350) which will power all the essentials in my house, including the central heating system. I have yet to "legally" tie the generator into the main panel, but I can disconnect the main and back feed the system if I must in a pinch. I also installed a plug on each of my boilers so I could directly power them as well should I need to. At least this way I don't have to worry about my pipes freezing.
  16. tinkabranc

    tinkabranc Minister of Fire

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    Please be safe! If you plan to use a generator on more than just your stove, get
    a transfer switch hooked up to your electric panel.
  17. Redox

    Redox Minister of Fire

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    I have tried a variety of inverters on just about everything in my house and except for a little noise on cheap electronics, all have worked fairly well. You may be able to clean up the output of a cheap inverter with an isolation transformer. There's a little insertion loss, but they round off the peaks in the square wave rather well.

    Chris
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